Physical activity plays a critical role in public health. Unfortunately, the prevalence of sedentary lifestyles is extremely high in the U.S., and there are well-established links between sedentariness and health risks such as obesity, diabetes, cardiovascular risks and certain cancers. Economic data suggest that physical inactivity and obesity account for nearly 10% of health-care costs in the U.S. In recent years many tailored lifestyle and exercise promoting programs have become available through the Internet, and it has been demonstrated that web-based exercise programs can effectively increase physical activity. However, it has also been shown that most programs (a) do not reach the target audience (i.e., in general people who need the program are less likely to use it),3 (b) fail to produce the frequency of contact needed for the program to be effective, (c) lack the capability of providing social support necessary to change behavior, (d) fail to tailor messages to specific, individualized behaviors, (e) do not directly address barriers to exercise, and (f) do not facilitate the formation of exercise habits. We therefore propose to (a) build upon and update an already proven to be efficacious, web-based exercise-promoting intervention that targets sedentary employees, and (b) innovatively integrate that program within an employee's daily workflow via the company's work-station productivity suite using a standard Application Programming Interface (API) recently released by Google (i.e., Google Apps Marketplace). The proposed program will be ever-present on the employee's desktop and seamlessly incorporated into the employee's everyday activities via Google Calendar and Gmail. A work/support group will be established based upon the employees that are in a defined user domain (e.g., department). The full integration with ubiquitous Google workplace applications will allow us to (a) reach a broad sedentary audience with fewer self- selection barriers to participation, (b) increase contact time (e.g., when the user logs into his/her account, he/she will be reminded of the planned physical activities for the day), (c) develop a highly tailored, personalized, and adaptive exercise plan based on the user's traits and characteristics (e.g., level of fitness, stage of change, exercise goals, exercise history, preference for specific exercise behaviors, reasons for exercising, approach or avoidance behavior, and perceived barriers), (d) integrate the exercise plan with calendar and email functions to prime behavioral intentions and potentially offer alternative behaviors in close time-proximity to the scheduled activity, (e) send tailored motivational messages, (f) send personalized feedback to the user, and (g) include social networking functionalities. Together these design features will promote regular physical activity and support forming a sustainable habit of regular physical activity. PUBLIC HEALTH RELEVANCE: The prevalence of sedentary lifestyles poses a significant and costly public health issue to the United States. This project builds upon and updates an already proven to be efficacious, web-based exercise- promoting intervention that targets sedentary employees. We propose to integrate a physical activity-promoting program with an employee's daily workflow via the company's work-station productivity suite using a standard Application Programming Interface (API) just released by Google (i.e., Google Apps Marketplace). This Google application has the potential to increase physical activity in the target group of sedentary workers.